static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
unsigned major, unsigned minor, int readonly,
int cdrom)
{
struct xen_vbd *vbd;
struct block_device *bdev;
struct request_queue *q;
vbd = &blkif->vbd;
vbd->handle = handle;
vbd->readonly = readonly;
vbd->type = 0;
vbd->pdevice = MKDEV(major, minor);
bdev = blkdev_get_by_dev(vbd->pdevice, vbd->readonly ?
FMODE_READ : FMODE_WRITE, NULL);
if (IS_ERR(bdev)) {
DPRINTK("xen_vbd_create: device %08x could not be opened.\n",
vbd->pdevice);
return -ENOENT;
}
vbd->bdev = bdev;
if (vbd->bdev->bd_disk == NULL) {
DPRINTK("xen_vbd_create: device %08x doesn't exist.\n",
vbd->pdevice);
xen_vbd_free(vbd);
return -ENOENT;
}
vbd->size = vbd_sz(vbd);
if (vbd->bdev->bd_disk->flags & GENHD_FL_CD || cdrom)
vbd->type |= VDISK_CDROM;
if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
vbd->type |= VDISK_REMOVABLE;
q = bdev_get_queue(bdev);
if (q && q->flush_flags)
vbd->flush_support = true;
if (q && blk_queue_secdiscard(q))
vbd->discard_secure = true;
DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
handle, blkif->domid);
return 0;
}
int vbd_translate(struct phys_req *req, blkif_t *blkif, int operation)
{
struct vbd *vbd = &blkif->vbd;
int rc = -EACCES;
if ((operation != READ) && vbd->readonly)
goto out;
if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
goto out;
req->dev = vbd->pdevice;
req->bdev = vbd->bdev;
rc = 0;
out:
return rc;
}
/*
* Write the physical details regarding the block device to the store, and
* switch to Connected state.
*/
static void connect(struct backend_info *be)
{
struct xenbus_transaction xbt;
int err;
struct xenbus_device *dev = be->dev;
DPRINTK("%s", dev->otherend);
/* Supply the information about the device the frontend needs */
again:
err = xenbus_transaction_start(&xbt);
if (err) {
xenbus_dev_fatal(dev, err, "starting transaction");
return;
}
err = xen_blkbk_flush_diskcache(xbt, be, be->blkif->vbd.flush_support);
if (err)
goto abort;
err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
(unsigned long long)vbd_sz(&be->blkif->vbd));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/sectors",
dev->nodename);
goto abort;
}
/* FIXME: use a typename instead */
err = xenbus_printf(xbt, dev->nodename, "info", "%u",
be->blkif->vbd.type |
(be->blkif->vbd.readonly ? VDISK_READONLY : 0));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/info",
dev->nodename);
goto abort;
}
err = xenbus_printf(xbt, dev->nodename, "sector-size", "%lu",
(unsigned long)
bdev_logical_block_size(be->blkif->vbd.bdev));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/sector-size",
dev->nodename);
goto abort;
}
err = xenbus_transaction_end(xbt, 0);
if (err == -EAGAIN)
goto again;
if (err)
xenbus_dev_fatal(dev, err, "ending transaction");
err = xenbus_switch_state(dev, XenbusStateConnected);
if (err)
xenbus_dev_fatal(dev, err, "switching to Connected state",
dev->nodename);
return;
abort:
xenbus_transaction_end(xbt, 1);
}
unsigned long long vbd_size(struct vbd *vbd)
{
return vbd_sz(vbd);
}